Introduction to Biochemical Treatment Methods for High Salt Wastewater by Manufacturers

High salt wastewater refers to wastewater containing at least 1% salt, which is mainly generated from the collection and processing of natural gas and petroleum. There are various substances in wastewater, including salt, oil, organic heavy metals, and some radioactive substances. Using biochemical methods for treatment, high concentrations of salt substances have inhibitory effects on the growth of organisms, and currently the main focus in China is on biological methods.

The process selection for biological treatment of high salt wastewater is basically the same as the ordinary process. The main processes include regulating tank, aeration tank, secondary sedimentation, sludge reflux, residual sludge dewatering, and addition of nutrients. At present, a simple treatment method for high salt wastewater is distillation desalination; This method is simple, easy to operate, and produces high-quality fresh water.

(1) Regulating pool

The regulating pool mainly considers the changes in the concentration of high salt wastewater. With the cycle of production fluctuations, it is important to focus on the changes in the salt content in the water and make corresponding adjustments.

(2) Aeration tank

According to the different types of salt in wastewater, traditional aeration methods are used for biological treatment of wastewater containing high levels of calcium chloride. Aeration should use diffusion aeration equipment with large bubbles.

(3) Secondary precipitation

There is a certain residual surface load, mainly considering the issue of density, which is not conducive to the sedimentation of sludge. When using activated sludge to treat calcium chloride, it is necessary to increase the reflux rate, reduce impact, and improve stability.

(4) Sludge dewatering

Due to the high content of calcium salts in the remaining sludge from high salt wastewater treatment, it is beneficial for dewatering and does not require the addition of coagulants. The final processed sludge is no different from ordinary sludge.

When treating calcium chloride wastewater, due to the high inorganic degree of activated sludge, it is not suitable for delayed aeration because the sludge has a long time and hydraulic retention time, which is prone to aging and affects the effluent results.